对UIToolbar进行子类化时崩溃

Question

我已经将UIToolbar子类化，以便更容易实现下一步的safari，上一步，完成的事情。当我直接添加它(即不是子类化)时，它工作得很好，但现在我添加了，每次我用-[keyboardToolBar hideKeyboard:]: unrecognized selector sent to instance点击按钮时，它都会崩溃这是我第一次尝试子类化，所以我不确定我是不是做错了什么。

子类的代码

@interface keyboardToolBar : UIToolbar {
UIToolbar *keyboard;
UIBarItem *previous;
UIBarItem *next;
UIBarItem *done;
}

@property (nonatomic, retain) UIToolbar *keyboard;
@property (nonatomic, retain) UIBarItem *previous;
@property (nonatomic, retain) UIBarItem *next;
@property (nonatomic, retain) UIBarItem *done;

-(void)previousField;
-(void)nextField;
-(void)hideKeyboard;


@end


#import "keyboardToolBar.h"


@implementation keyboardToolBar
@synthesize keyboard, previous, done, next;

-(UIToolbar*)initWithFrame:(CGRect)frame{
//Create a new toolbar
keyboard = [[UIToolbar alloc]initWithFrame:frame];

//Create all the buttons and point them to methods
UIBarButtonItem *previousButton = [[UIBarButtonItem alloc] initWithTitle:@"Previous" 
                                                            style:UIBarButtonItemStyleBordered 
                                                            target:self 
                                                            action:@selector(previousField:)];
UIBarButtonItem *nextButton     = [[UIBarButtonItem alloc] initWithTitle:@"Next" 
                                                            style:UIBarButtonItemStyleBordered 
                                                            target:self 
                                                            action:@selector(nextField:)];
UIBarButtonItem *filler     = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace 
                                                            target:nil 
                                                            action:nil];
UIBarButtonItem *doneButton     = [[UIBarButtonItem alloc] initWithTitle:@"Done" 
                                                            style:UIBarButtonItemStyleBordered 
                                                            target:self 
                                                            action:@selector(hideKeyboard:)];

//Set the width of both of the buttons to make it look pritty
previousButton.width = 70.0f;
nextButton.width = 70.0f;

self.previous = previousButton;
self.next = nextButton;
self.done = doneButton;

//Add the buttons to the toolbar
[keyboard setItems:[[[NSArray alloc] initWithObjects:self.previous, self.next, filler, self.done, nil] autorelease]];


//Release the buttons
[previous release];
[next release];
[filler release];
[done release];


//return the shiny new toolbar
return keyboard;
}

-(void)previousField{

}

-(void)nextField{

}

-(void)hideKeyboard{
NSLog(@"hello");
}


@end

，并使用UIToolbar *keyboard = [[keyboardToolBar alloc] initWithFrame:CGRectMake(0, 0, self.view.bounds.size.width, 50)];调用

我已经尝试了我能想到的所有方法，但仍然得到相同的错误。我确信我只是没有把按钮指向错误的地方，但任何帮助都会非常感谢，谢谢Darc

Answer 1

您(或您正在做的事情)正在调用hideKeyboard: (注意冒号，表示该方法只有一个参数)。但是，您实现的hideKeyboard方法不接受任何参数。

最有可能的情况是，hideKeyboard应该更改为：

- (void)hideKeyboard:(id)sender {
   NSLog(@"hello");
}

顺便说一句，通常的类名样式是大写的，所以你的子类应该是KeyboardToolBar (我也建议保持和苹果的类一样的驼峰大小写，所以KeyboardToolbar是最好的)。

Answer 2

这里的问题是，您的按钮正在调用接受输入的函数，但您的函数不接受输入：

UIBarButtonItem *doneButton     = [[UIBarButtonItem alloc] initWithTitle:@"Done" 
                                                            style:UIBarButtonItemStyleBordered 
                                                            target:self 
                                                            action:@selector(hideKeyboard:)];

这意味着必须有一个方法hideKeyboard:(id)sender。但是你有

-(void)hideKeyboard{
NSLog(@"hello");
}

将输入添加到函数或从选择器调用中删除:。

Answer 3

你有效地把它写成了一个类方法，由于内存管理等问题，这里是一个更好的版本。

-(UIToolbar*)initWithFrame:(CGRect)frame{ //新建工具栏

if ((self = [super initWithFrame:frame]))


//Create all the buttons and point them to methods
previous = [[UIBarButtonItem alloc] initWithTitle:@"Previous"  style:UIBarButtonItemStyleBordered target:self  action:@selector(previousField:)];

next  = [[UIBarButtonItem alloc] initWithTitle:@"Next" style:UIBarButtonItemStyleBordered  target:self  action:@selector(nextField:)];
UIBarButtonItem *filler     = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace  target:nil  action:nil];
done     = [[UIBarButtonItem alloc] initWithTitle:@"Done"  style:UIBarButtonItemStyleBordered target:self action:@selector(hideKeyboard:)];

//Set the width of both of the buttons to make it look pritty
previous.width = 70.0f;
next.width = 70.0f;

//Add the buttons to the toolbar
[keyboard setItems:[[[NSArray alloc] initWithObjects:previous, next, filler, done, nil] autorelease]];


//Release the buttons
[previous release];
[next release];
[filler release];
[done release];


//return the shiny new toolbar
return self;
}

还要将您的方法修复为@selector(someAction)以匹配-(void)someAction;或@selector(someAction:)以匹配-(void)someAction:(id)sender;

也没有理由保留对UIToolBar *键盘的引用，因为您希望引用的是自己。实际上，可能根本没有理由保留对按钮的引用，除非您稍后需要更改它们的标题或操作/目标对。